The purpose of this study is to determine if treatment with a medication belonging to a class of drugs called AT-1 receptor antagonists (AT1R) is associated with a beneficial effect on vascular function in an elderly cohort of patients. Healthy patients above the age of 70 will be assigned to treatment with this medication or placebo (dummy pill) for a period of six weeks. At the end of this treatment phase patients will be taken off their respective treatments and placed on the opposite arm for an additional period of six weeks after a wash out period of 1 week. The end point of improvement in vascular function will be assessed by high resolution ultrasound measurements of brachial artery dimensions in response to inflation of a blood pressure cuff in the arm for a duration of four minutes and is completely non-invasive. Previous studies have documented the close association between peripheral and coronary endothelial function. Endothelial function determined in this fashion has been shown to be a predictor of cardiovascular risk and is therefore a useful surrogate endpoint in clinical trials.